1. Field of the Invention
The present invention relates to a command executing method of an information reproducing apparatus, a record medium for recording a program that causes an information reproducing apparatus to execute a command, and a disc reproducing apparatus for reproducing data from an optical disc such as a CD-ROM or a DVD.
2. Description of the Related Art
In recent years, as data communications using public telephone lines such as Internet are becoming common, computer viruses that are programs that are not issued by users cause computer systems to malfunction and are becoming serious social problems.
Most of peripheral units such as a CD-ROM drive and a DVD drive that are operated corresponding to commands received from host computers cannot know whether such commands have been infected by computer viruses. Thus, the peripheral units simply receive and execute the programs infected by computer viruses.
To prevent an optical disc drive such as a CD-ROM drive or a DVD drive from being operated with a program infected by a computer virus, a method for restricting the operation of the optical disc drive with a password designated to each user or each disc title has been proposed.
However, in such an optical disc drive, a program infected by a computer virus may cause setting information such as a password to be erased or forged. Once an optical disc drive is infected by a computer virus, the optical disc drive may not be used.
In such circumstances, a means for securely protecting an optical disc drive from a program infected by a computer virus has been desired.
The present invention is made from the above-described point of view. An object of the present invention is to provide a disc reproducing apparatus that prevents a command of a virus-infected program that resides in a computer system from being executed.
Another object of the present invention is to provide a command executing method for an information reproducing apparatus so as to prevent a virus-infected program that resides in a computer system from disturbing the operation of the information reproducing apparatus.
A further object of the present invention is to provide a record medium for recording a program that causes an information reproducing apparatus to prevent a virus-infected program that resides in a computer system from disturbing the operation of the information reproducing apparatus.
The present invention is a command executing method of an information reproducing apparatus, comprising the steps of receiving through a first transfer path a command for managing the operation of a reproducing portion that reproduces information, determining whether or not to validate the execution of the command received through the first transfer path corresponding to information obtained through a second transfer path, and executing the command when the execution of the command is validated.
Thus, according to the present invention, as a condition for executing a command issued from a command generating unit of a host unit or the like, since a command received from a path that the command generating unit does not know is added, a command forged by a computer virus that resides in the command generating unit can be prevented from being executed. Consequently, a disc reproducing apparatus that is highly secured can be provided.
These and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of a best mode embodiment thereof, as illustrated in the accompanying drawings.